the role of biopesticides in sustainable agriculture
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The role of biopesticides in sustainable agriculture
Susan M. Boyetchko Agriculture and Agri-Food Canada, Saskatoon, Saskatchewan,CanadaSue.Boyetchko@Canada.ca
Nature fighting nature
Introduction• Investment in biopesticide R&D in Canada has
progressed • perceptions and attitudes towards chemical pesticides
have changed• renewed interest in biopesticides, more products
being registered since 2000• social and economic drivers
– legislative changes– regulatory policies– changing attitudes of consumers– greater interest by small-to-medium sized
enterprises (SME’s)
What are biopesticides?• beneficial use of living organisms to (directly or
indirectly) suppress, inhibit, damage, or kill a pest or pest population
• biocontrol agents: e.g. fungi, bacteria, viruses, natural products
• inundative application, applied repeatedly, annually
• easy to use and mass-produce, acceptable shelf life
• host specific (target pests/pathogens, group of related pathogens)
• no detrimental effects on non-target organisms• environmental and toxicological safety standards
Biopesticides – Opportunities/Need• pesticide-resistance management• control of invasive alien species• reduced risk pest control products (new active
ingredients & new modes of action)• expand label registration of existing biopesticide
products; more products registered in Canada• reduce chemical residues (soil, water, food)• IPM in crop production systems (e.g. conventional,
organic, no/low pesticide use)• where control measures (e.g. chemicals) are
inadequate/unavailable/deregisteredBiopesticides = Next Generation of Pest Control
Products(transformative research)
Biopesticide MarketGlobal Biopesticides and Synthetic Pesticides Market
($millions)Type 2003 2004 2005 2010 Ave. Ann.
growth rate
Biopesticides 468 562 672 1,075 9.9Synthetic 27,144 26,600 26,076 24,205 -1.5
PesticidesTotal 27,612 27,162 26,748 25,280 -1.1Biopesticides
as % of total 1.69 2.07 2.51 4.25
from Business Communications Company, Inc.(www.bccresearch.com)
Growth in the biopesticide market is expected to be 10X greater than for synthetic pesticides.
Olson 2015
Perceptions of biopesticides in comparison to chemicals• biopesticides have lower efficacy • pest control not as rapid as chemicals• narrow spectrum of activity with biologicals (market size)• how to expand spectra of activity• biopesticides are more difficult to use• chemicals provide “silver-bullet” approach/one-time use• consumers/producers are risk-averse and have few
reasons or incentives to change pest control practices• biased comparisons are made between biologicals and
chemicals• agricultural crops and home-gardens must be pristine
and weed-free
How do we change these perceptions and improve adoption of biopesticides?• Invest in Research & Development
– build research expertise, capacity– assemble multidisciplinary teams
• Establish Critical Mass– develop effective partnerships between government,
academia, and industry– expertise in microbiology, plant pathology, weed
science, agronomy, chemistry, engineering• Create Education and Communication Programs
– public awareness and outreach programs– general public, producers, extension personnel,
industry– early education in schools and universities
Product Development –Strategy
Microbial Agent(selection & improvement,
mode of action)
Formulation
Application TechnologyFermentation
Field TrialsValidation ofTechnology
Platform technologies:fermentation, formulation, spray application
Stag
e ga
tes
Biopesticides – Science Innovation ChainOur Road Map
Del
iver
able
s
scientific knowledge
Discovery and BCA selection
Proof of concept
greenhouse, field efficacy
Technology development
fermentation, formulation,
stability
Market identification
markets & uses
Technology transfer
license agreements
Application development
large-scale field tests;
product formulation
Commercial scale-up
manufacturing, process
engineering
Technology adoption
product sales; client adoption
Registration
biopesticide product
Basic science and concept design
Applied research
Regulatory process
Advanced knowledge
Greater Investment• Biopesticide industry becoming better
organized (e.g. BPIA); meet with key regulators• Acquisition of biopesticide SME’s by multi-
nationals– BASF Becker Underwood– Bayer CropScience AgraQuest & Prophyta– Syngenta Pasteuria BioScience– Monsanto Novozymes
• Licensing technology from government and university scientists
It starts with fermentation…Liquid-state
SRC pilot plant
Solid-state
Biphasic systems
Formulation Criteria• Compatible with biopesticide; not phytotoxic to crop• Facilitate dispersal, deposition and retention• Promote efficacy on the target• Protect from shear forces during spray• Protect against heat, desiccation, and UV radiation• Stability during production and storage• Amenable for commercial packaging & handling
Apply through conventional farming equipment.• Improve safety to users and environment
Composition: Active ingredient – biological agent, metabolites
Carriers – clay, peat, oil, grain, inerts, biofilms, water (separate or integrated with biological)
Adjuvants – humectants, dispersants, stickers, spreaders, binders, surfactants, synergists, nutrients, sunscreens
Type: Granules: made from solid or liquid fermentations
Wettable powders: dehydrated liquids-spray dryers
Oil-based emulsions: water-oil-water (WOW)
Micro-encapsulation of solids or liquids
Endophytes• Fungi or bacteria that occur and develop inside
plant tissues without causing harm • Microbes with biocontrol properties• Overcome delivery/application issues associated
with biopesticides• Cheaply introduced into seeds, tissue culture
plantlets• Provide protection against adverse environment
conditions• Possess additional beneficial properties (accelerate
plant emergence), plant growth promotion
Natural products• Sophisticated technology: bioassay
directed; NMR, UPLC-MS, GC• Use of databases to determine if known or
unknown natural products
Natural Products: Direct Bioautography
17
Spot bacterial extracts on TLC plate
Liquid chromatography
Preliminary chemical analysis
Harvest pathogen for inoculum
Put inoculum in chromatography sprayer
Isolation and structuralelucidation
Bio-activity and IC50 testing
Research Projects• Soil bacteria as a pre-emergent bioherbicide
(Susan Boyetchko, Russell Hynes)• Waging a war on potato late blight: a biological
solution for a global disease (Susan Boyetchko, Patrice Audy, Tim Dumonceaux, Chris Kirby, Ting Zhou)
• Biopesticides as a Novel Management Strategy for Sclerotinia in Canola (Susan Boyetchko, Chrystel Olivier, Fengqun Yu, Tim Dumonceaux, Abdulsalam Dakouri, Chris Kirby)
Pre-emergent soil bacteria as bioherbicides for annual grass weeds - Pseudomonas fluorescens strain BRG100
• Wild oat and green foxtail– 2 most important grass
weeds in Canadian prairies/Great Plains region
– Soil bacteria applied as pre-emergent bioherbicides
– large-scale field productionControl Treated with bacteria
Susan Boyetchko & Russell Hynes
Canadian and US patents issued
Pseudomonas fluorescens strain BRG100Annual grass weed control
• early proof-of-concept• field validation• mini-plots (1 or 2 m2 plots)• seeded weeds by hand; pre-determined
weed densities
Green Foxtail - untreated Green Foxtail - BRG100
Soil bacteria – growth stage
0
10
20
30
40
50
60
70
80
Roo
t sup
pres
sion
(%)
0 3 6 9 13Plant growth stage (days)
4 dai
6 dai
8 dai
Growth stages:0 = germination3 = 1 leaf stage6 = 1-2 leaf stage9 = 2 leaf stage13 = 2-3 leaf stagedai = days after inoculation
• susceptibility at germination to early root growth• no effect as a foliar spray or beyond 1-2 leaf stage• pre-emergent application•Broad spectrum activity on other grass weed species
Compound % Inhibitionethyl acetate extract 63 ± 6
(0.6 mg/ml)Pseudophomin A 67 ± 6
(5 x 10-4 M)Pseudophomin B 30 ± 4
(5 x 10-4 M)
Pseudophomin A (C55H98N9O16); Pseudophomin B (C57H102N9O16)J.W. Quail, N. Ismail, M.S.C. Pedras, S.M. Boyetchko. 2002.
Acta Cryst. C58:o268-o271
Green foxtail in wheat with Pseudomonas as a pre-emergence application - 2006 field trials
Untreated Low-rate High-rateGet the critical number/pop’n of BRG100 at the right place & timeHow are the bacteria dispersed from the pesta?Will crop competition enhance bioherbicidal potential? Where do we place the granules?
Susan Boyetchko & Russell Hynes
Potato Late Blight – Phytophthora infestans• Multi-billion dollar industry worldwide• Seeded potatoes in Canada – 373,000 acres
(2012)• In Canada, potato production represents a market
value of $1 billion; larger market of $5.5 billion for food processors
• Annual crop losses & cost of effective control measures ~ $6.7 billion globally
• Caused Irish potato famine in 1840s• Multidisiplinary team (plant pathology, chemistry,
microbiology, genomics, fermentation, formulation)• Two 3 year projects• Filed PCT patent• Industry partner – agreement with option to • license
Why should we pursue biopesticides for late blight?• New genotypes of the pathogen in Canada and
the U.S. (US-8 US-23); CA09• Fungicide-insensitive isolates (metalaxyl,
mefenoxam, etc)• Multiple fungicide applications per growing season
– Up to 12-15 applications per season– Cost millions per fungicide application
• Chemical pesticide load in environment• Food safety and quality
1H NMR of 189B vs. 189C
189B 189C189B
Control of Phytopthora infestans with Pseudomonas chlororaphis strain 189
189 pathogen alone
Comparison of efficacy with other control methods (synthetic fungicide & biopesticides)
Actinovate Dithane
Rhapsody Serenade
Sclerotinia sclerotiorum in canola• Canola is a multi-billion dollar industry in
Canada• Yield losses of 5-10%; up to 90% in 2010• Full resistance to Sclerotinia sclerotiorum in
canola remains elusive• Synthetic fungicides show only single-site
activity• Chance of resistance to chemical fungicides• Investigate green alternatives to chemicals
as a clean technology for the canola industry
Objectives• Screen and evaluate biopesticides (in
vitro, in vivo)• Conduct molecular characterization of the
biopesticide candidate to improve its performance
• Understand the biopesticide mode of action (antifungal compounds, direct effect)
• Understand plant defense mechanisms• Evaluate efficacy (does it work?)
Treatment Ascospore # of sclerotia Sclerotial (% CFCF) Germination weight (g)0 100 a 41.3 a 0.009 a10 0.0 b 0.0 b -25 0.0 b 0.0 b -50 0.0 b 0.0 b -
Effect of Bacterial strain on Sclerotinia sclerotiorum
Treatment Ascospore # of sclerotia Sclerotial(% CFCF) Germination weight (g)0 100 a 39.8a 0.010 a10 0.0 b 0.0 b -25 0.0 b 0.0 b -50 0.0 b 0.0 b -
Bacterial strain PENSV20
Bacterial strain CARAF5
Treatment Ascospore # of sclerotia Sclerotial (% CFCF) Germination weight (g)0 100 a 26.3 a 0.011 a10 0.0 b 13.3 bc 0.009 a25 0.0 b 0.0 c -50 0.0 b 0.0 c -
Effect of Bacterial strain on Sclerotinia sclerotiorum
Treatment Ascospore # of sclerotia Sclerotial(% CFCF) Germination weight (g)0 100 a 38.2 a 0.010 a10 95.8 a 36.7 a 0.012 a25 99.2 a 36.7 a 0.011 a50 101.4 a 39.0 a 0.013 a
Bacterial strain CARAF4
Bacterial strain YGM broth
Understand plant defense mechanisms• Westar and Topaz (susceptible)• Zhongyou 821 (partial resistance)• Treatments: pathogen alone, BCA 24 h
before pathogen, BCA 24 h after pathogen, sterile water
• Canola plants sprayed at 30% flowering stage with ascospore suspension
• RNA sequencing• Canadian Light Source Synchrotron
Biopesticide for Sclerotinia
Multi-level biological systems require multidisciplinary approaches
Application Technology
EpidemiologyEcology
EpizoologyBiopesticides
Pest Biology & Physiology Agronomy and IPM
Synergy with ChemicalsFormulation Chemistry
Microbial Physiology(Fermentation)
Use of Integrated Pest Management tools will lead to successful adoption of biopesticides
So what is the future of biopesticides?
• finding a microbial agent is “easy”
• discovering a “potential” biological control agent with all the desirable characteristics is much harder
“If it was easy, everyone would be doing it”
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